Data centers include rows of stacked computer and/or communication systems. For cooling purposes, the computer systems draw air from the surrounding environment into the systems at one side (e.g., the front) and exhaust the air out of the systems at another side (e.g., the back). A data center may include an arrangement of hot aisles and cold aisles in order to increase the cooling efficiency of the data center. By mounting a row of the stacked computer systems in the same direction, cold air from the cold aisle will flow into the systems, and hot air will exhaust out of the systems to the hot aisle.
For the hot and cold aisle arrangement, two versions of each type of computer system (e.g., two versions of a switch), one version that provides front-to-back airflow and another version that provides back-to-front airflow, may be produced. One or more fans may be fixed in version-specific orientations in each version of the stacked computer systems to provide the respective front-to-back or back-to-front airflow. The version of the computer system (e.g., front-to-back or back-to-front) installed in a data center may depend on the location of the computer system within the data center (e.g., hot aisle or cold aisle).